SNLA434 November   2023 DP83TC812R-Q1 , DP83TD510E , DP83TG720R-Q1 , LMK1C1103 , LMK1C1104 , LMK5B12204 , LMK6C

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Power Supply
    1. 2.1 Internal Supply Rails
    2. 2.2 External Supply Lines
    3. 2.3 Requirements for PoDL
    4. 2.4 Clocking
      1. 2.4.1 Topology 1
      2. 2.4.2 Topology 2
  6. 3Summary
  7. 4References

Abstract

This application note provides guidance for good schematic and layout practices for passing EMI and EMC tests. The publication focuses on the often neglected aspects of power supply and clocking schemes. A special focus is also set on the requirements for singe pair Ethernet (SPE) with adding power over data lines (PoDL) on top, as this has additional requirements on the ripple voltage caused by the power supply on the data line.